Instrument panels, console boxes, glove boxes, etc. which are provided on an interior side of a vehicle are correctively called “interior members”, while bumpers, etc. which are provided on an exterior side of the vehicle are called “exterior members”. The interior members and the exterior members may be made of decorated molded articles. The decorated molded articles consist of a resin substrate molded of a synthetic resin material and a decorative sheet bearing a decorative pattern and applied to a front or obverse side of the resin substrate.
The decorative sheet is a design member made of a resin sheet having a woodgrain-tone or a leather-tone, a resin sheet integrated with a foamed resin, a cloth, an unwoven fabric, etc. The decorative sheet as applied to the resin substrate can improve appearance design property of the interior members or the exterior members.
Techniques for applying a decorative sheet to a resin substrate are known as disclosed, for example, in Japanese Patent Application Laid-open Publication (JP-A) No. H04-288214. According to the technique disclosed in JP H04-288214A, a decorative sheet is held between an upper molding chamber and a lower molding chamber. Internal spaces of the upper and lower molding chambers, which are separated by the decorative sheet, are evacuated into a vacuum state. The decorative sheet is heat-softened and then placed over the upper surface of a resin substrate held inside the lower molding chamber. Thereafter, the outside air is introduced into the upper molding chamber whereupon the decorative sheet is caused to closely adhere to the resin substrate due to a pressure difference created during a vacuum pressure molding process.
The technique disclosed in JP H04-288214 is successful when used in combination with a resin substrate having a constant cross section. However, because many interior or exterior members have corner sections, the disclosed technique would encounter a problem that a decorative sheet is caused to gather into folds and creates wrinkles at a corner section of the resin substrate.
To deal with this problem, an improved technique has been proposed as disclosed in Japanese Patent Application Laid-open Publication (JP-A) 2010-23245. According to the improved technique, a projection is provided on an internal or recessed corner section of a resin substrate for suppressing generation of wrinkles such that when covered with a decorative sheet together with the corner section, the projection takes up or absorbs an excess part of the decorative sheet created at the corner section being covered with the decorative sheet. However, since the projection protrudes from a general surface of the resin substrate, a mating part or component, which is used in combination with a decorated molded article including the resin substrate, is required to have a recess or an opening for receiving the projection to enable attachment of the decorated molded article to a vehicle body. The projection thus constitutes a restriction on the shape and design of the mating component.
Furthermore, the projection provided on the corner section brings about a slight increase in weight of the decorated molded article. In addition, due to the presence of the projection, storage of the resin substrates in a stacked state requires spacers provided between adjacent resin substrates for protection of the projections. The production efficiency of the resin substrates is therefore relatively low.
It is an object of the present invention to provide a decorated molded article which is capable of preventing generation of wrinkles without increasing the weight of the decorated molded article and constituting any restriction on the shape and design of a mating component.